Re: NSPredicateEditor

FROM : Kimo
DATE : Thu Jan 24 21:47:55 2008

On Jan 7, 2008, at 4:08 PM, Peter Ammon wrote:
>
> On Jan 7, 2008, at 3:34 PM, Kimo wrote:
>

>> I'm using the NSPredicateEditor template in IB, and it works well. 
>> The exception is with a BOOL value.  For example, if I have a BOOL 
>> value called flag, and I want to use the string (flag == 1), 
>> however, using the NSPredicateEditor always produces the string 
>> (flag == "1") which doesn't work.  Is there an option to create the 
>> string without the quotes?  Or is there some setting in 
>> NSPredicateEditor I'm not aware of?
>> TIA.

>
> Hi Kimo,
>
> If you want to have the boolean option be represented by a text 
> field, you can of course just select the Numbers type for the right 
> expression.  That will coerce the right expressions to a numeric 
> type and give you a string like flag == 1.
>
> If (more likely) you want the boolean value to be represented by a 
> popup, this can't yet be configured in IB, but it is easy to do 
> programmatically.  Create an NSPredicateEditorRowTemplate with left 
> expressions your key path expressions, and right expressions as 
> constant expressions containing your boolean values.  Then you can 
> configure the view titles and all the rest by modifying the 
> templateViews.
>
> Let me know if you have any questions,
> -Peter
>


Hi Peter,

That helped a lot, thank you.  I have another question.  I created 
(programmatically) a NSPredicateEditorRowTemplate so that the left 
popup button has "Start Date" and "End Date."  The middle popup button 
has "is today" and "is the date" and "is before the date."  The right 
expression is a NSDatePicker.  However, when the user selects the 
operator "is today" I want the NSDatePicker to be hidden, and then 
visible for the other two operators.

I see other apps do this (Mail for example), but I can't seem to 
accomplish the same thing.  I subclassed NSPredicateEditorRowTemplate 
so I could alter the templateViews, but I can't seem to determine 
which middle popup is selected.  What is the best way to hide the 
NSDatePicker when the user selects the menu item "is today" and then 
displays it for the other menu items?

Thanks in advance!
-Kimo